Syndicated columnist Mark Shields and New York Times columnist David Brooks join Judy Woodruff to discuss the week’s news, including the latest developments in the Russia probe and how President Trump has been reacting to reports that he is being investigated for possible obstruction of justice, plus the state of political polarization in light of a shooting targeting GOP lawmakers.

DAVID BROOKS: To me, we have had this — the idea that there has been collusion between the Russians and the Trump campaign has been investigated for a long time. And so far, we have had no really serious evidence that they did collude, and everything else seems to be leaking out.

So, I begin to be a little suspicious — and maybe I’m wrong — we will see over the long term — whether there was any actual act of collusion. There were certainly conversations maybe about some building and some investment, but so far, no evidence of an underlying crime.

But this, to me, is not a criminal story. It is a psychological story. And it’s a story about a president who seems to be under more pressure, under more threat, lashing out in ways that are painfully self-destructive, but also extremely disturbing to anybody around him.

And so whether it’s the North Korean Cabinet hearing that he held recently, where they all had to praise him, or the tweets as late as this morning, this is not a president who is projecting mental stability.

And the idea that he will fire somebody, whether it’s Mueller or anybody else, seems very plausible. And so, to me, if there is something really damaging here, it’s something that has not yet happened caused by the psychological pressure that he apparently feels.